The Proposed study will examine interrelations and dependencies between infants' habituation performance and expectation formation. Habituation is thought to reflect cognitive processes such as information encoding and memory. Expectancy formation is thought to index the infants' learning of a rule regarding the spacial aspects of stimuli presentations. Based on the theory that both habituation and expectancies are cognitively rooted, and, to some extent, reflect infant learning, it is hypothesized that infants who are faster habituaters will more readily form visual expectations as indexed by a sharper decrease in visual reaction times to stimuli presentations and more anticipatory looks towards future stimulus locations. To test this, 50 5-month old infants will be administered an infant-control habituation paradigm and a visual expectation paradigm during a laboratory visit so that individual performance in the two paradigms might be compared. Study 2 tests a functional interpretation of visual expectancy formation. It has been hypothesized that visual expectancies are ecologically adaptive in that they facilitate learning by preparing the infant for incoming stimulation, To test this, 50 infants will be assigned to one of two groups: one in which stimulus presentation is spacially regular, and another where stimulus presentation is random. It is expected that infants in the spatially regular condition will be more apt to form expectations than infants in the irregular condition, and consequently, this increased preparatory set will facilitate their learning of a target visual feature.